It's a fishy business

THE success of Andrew Carroll's Palmers Island mulloway farm could provide the springboard for North Coast prawn farmers to diversify their operations to compete with cheaper imported prawns flooding the market, research has found.

After purchasing a disused prawn farm in 2008, Mr Carroll has taken his operation has gone from strength to strength, with demand for his mulloway from Australia's top chefs skyrocketing on the back of his quality product and him being crowned 2010 NSW Young Farmer of the year.

A recent research trial funded by the Rural Industries Research and Development Corporation at his farm has shown that mulloway - otherwise known as jewfish - can be successfully farmed using the infrastructure of existing prawn farms.

The trial, led by Dr Jeffrey Guy from Southern Cross University's National Marine Science Centre, took a "pond-to-plate" approach which covered the breeding of mulloway fingerlings, growing the fish out to market size and testing the quality of the final cooked product.

Mr Carroll raises his fingerlings in one of four covered ponds before being transferred to one of eight other ponds on the farm till they reach maturity, weighing around 2.1 kilos at two years.

Dr Guy wants the mulloway research trial to encourage some of the larger Palmers Island prawn farms to diversify their production base and improve their longer-term viability.

"Our research has shown that mulloway perform extremely well in prawn ponds, reaching market size in two years, with high survival, good growth, minimal disease and high production rates approaching 14 tonnes per hectare," Dr Guy said.

"We also found mulloway to be a hardy species when grown in earthen ponds; they were very resilient to periods of poor water quality and no significant outbreaks of disease were recorded, so this may be the preferred culture environment for this species.

"Other positive findings were that the mulloway were easy to harvest and transfer - a major advantage in the farming of this species - and were extremely well received in the marketplace."

Dr Guy said mulloway was also found to have valuable health benefits for those who consume the popular fish.

"Analysis of the farmed mulloway fillets showed they were an excellent source of long chain omega-3s and also contained high levels of the monounsaturated omega-9 fatty acid, oleic acid, providing important health benefits for consumers," he said.

Despite the positive research results, Dr Guy said their research identified several limiting factors to mulloway farming.

"Key constraints include a lack of knowledge about diets, feeding protocols and the effects of environmental parameters, such as temperature and salinity, on feed intake," he said.

"The research trial also identified the poor availability and high cost of juvenile fish for grow-out."

But work is already under way to find ways to make mulloway farming economically viable.

"A new RIRDC-funded research project commenced earlier this year to look at the major cost areas of diets, feeding and fingerling production."

Yesterday The Daily Examiner attempted to contact three Palm- ers Island-based prawn farms to ask if they were considering diversifying their aquaculture operations to include mulloway farming.

Despite having the facilities and a licence to farm fish, Tru Blu Prawn Farms owner Frank Roberts said he would not be going into farming mulloway as it was not as lucrative as prawn farming.

"Prawn farming at the moment is worth nothing, but mulloways farming is worth a damn sight less," he said.

"I have the perfect set-up but there is just not the money in mulloway farming."

Both Fortune Prawn Farm and Ausfarm Aquaculture did not respond to the Examiner's inquiries by close of business yesterday.

The "Re-invigorating NSW prawn farms through the culture of mulloway" publication can be downloaded for free from www.rirdc.gov.au.